Referring to FIG. 1, a conventional football includes an outer cover 1 and a single lace 2. The outer cover 1 has a plurality of lace holes 101 arranged in pairs spaced apart from each other along a longitudinal direction (X). After the lace 2 is laced through the pairs of lace holes 101, the lace 2 is formed with a plurality of transverse lace portions 201 spaced apart from each other along the longitudinal direction (X), and two longitudinal lace portions 202 disposed side by side and extending through the transverse lace portions 201. This configuration increases the friction force during throwing of the football by a user.
Referring to FIGS. 2 to 4, during making of the aforesaid conventional football, the lace 2 is extended through the pairs of lace holes 11 in sequence and in a spiral manner. That is, after the lace 2 is extended through one of the pairs of lace holes 101 twice and is tightly pulled to form one of the transverse lace portions 201, the lace 2 must then be moved obliquely toward the next adjacent pair of lace holes 101 so as to extend smoothly therethrough and form the next transverse lace portion 201. Since the length of the single lace 2 is long, an end of the lace 2 must be found every time the lace 2 is to extend through a corresponding pair of lace holes 101, so that a lot of time is consumed, thereby adversely affecting the production efficiency of the conventional football. Further, as shown in FIG. 4, uneven forces may be applied during pulling of the transverse lace portions 201, so that the transverse lace portions 201 are not uniformly tightened. As such, each transverse lace portion 201 may have a width (W) measured along a transverse direction (Y) transverse to the longitudinal direction (X) different from that of the other transverse lace portion 201. Further, a distance (D) between two adjacent ones of the transverse lace portions 201 may be different from a distance (D) between another two adjacent ones of the transverse lace portions 201. In addition, the outermost ones of the transverse lace portions 201 may slide out of two opposite ends of the longitudinal lace portions 202 due to uneven pulling forces or poor production control.